Door latch



Patented May 6, 1947 UNITED STATES PTENT OFFiCE DOOR LATCH Harrison 0. Gilbert, Elmira, N. Y., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application March 23, 1944, Serial No. 527,789

2 Claims. 1

The present invention relates to a door latch and more particularly to a combined spring and latch securing mechanism for the hinged door of an automatic rifle feed mechanism.

Feeding mechanisms for automatic rifles which are mounted directly on the body of the gun are subjected to severe vibration during operation of the gun. In that type of feeding mechanism which employs an ammunition belt, the vibration and other causes sometimes effect a dislocation of the movable parts such as to interfere with the operation. In such cases, it is necessary for the operator to obtain access to the interior of the mechanism in order to take the proper corrective measures.

In one form of feeding mechanism, access to the interior is provided by means of a hinged door adjacent the belt link discharge chute, the door being closed by a spring and retained by a latch. Some difficulty has been encountered in providing a latch which will withstand the vibration and impacts encountered in use, and failure of the latch to hold the door closed has resulted in a piling up of the belt links in the opening with consequent jamming of the feeding mechanism.

It is an object of the present invention to provide a novel door closing and securing mechanism which is effective and reliable under severe vibration and battering,

It is another object to provide such a device including a spring element for closing the door which element also functions to hold the latch in operative position.

It is a further object to provide such a device in which the spring element is arranged to exert closing pressure on the door and at the same tim to yieldingly resist releasing movement of the latch in a plane perpendicular to the direction of said pressure.

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawing, in which:

Fig. 1 is a side elevation of a feeding mechanism for an automatic rifle showing a preferred embodiment of the invention applied thereto, and

Fig. 2 is an end view of the same.

In Fig. 2 of the drawing, there is illustrated a housing I of generally cylindrical shape having a receiving chute 2 on one side, a belt link discharge chute 3 on the other side and a cartridge feed chute 4 on its bottom which latter also forms part of an attaching means for mounting the 2 feeding mechanism on an automatic rifle not illustrated.

The belt link discharge chute 3 is provided with a door 5 best shown in Fig. 1 hinged at its upper end as indicated at 6 on a tie-bolt 1 of the feeding mechanism. The door 5 provides access to the discharge chute and the adjacent portion of the interior of the feeding mechanism, thereby enabling the operator to correct any dislocation or jamming of the working parts of the feeding mechanism.

Yielding means are provided for urging the door toward closed position in the form of a spring 8 having terminal portions 9 and H coiled about the tie-bolt 1 with the ends 12 and I3 resting against the casing I while the intermediate portion [4 presses on the door to move it into closed position.

According to the present invention, means are provided for locking the door closed, in the form of a latch i5 which is slidably pivoted on the door 5 as by means of a flanged rivet I6 fixed in the door loosely traversing the latch and which is provided with a bifurcated portion H at its lower end adapted to engage under a catch or button is fixed in any suitable manner on the discharge chute 3. Sliding movement of the latch [5 on the door is limited as by engagement of the stem l9 of the rivet [6 in a slot 2| of the latch.

The dimensions of the slot 2i and the bifurcated portion I! of the latch and of the button I8 are such that the latch can be withdrawn vertically from the button only to such an extent as to disengage the bifurcated portion from the shank 22 of the button. Movement of the latch out from under the flange of the button may then be accomplished by a pivotal movement of the latch about the rivet IS.

The upper end of the latch 15 is bent in the form of a loop 23 for facilitating manipulation of the latch, and a tongue 24 is struck out from the end of the latch so as to form with said loop 23 a seat for the mid portion of the door spring 8. As best shown in Fig. 1, the mid portion Id of said spring is bent upwardly in a U-shape, the center of which engages in the seat formed by the tongue 26 of the latch, whereby the resiliency of the spring presses the latch downwardly. At the same time, the centering effect of the inclined portions 25, 26 of the central part of the spring 8 yieldingly resists rotation of the latch away from its Vertical position. The spring 8 thus serves to resist both the sliding and the pivotal movements of the latch necessary to disengage it from the button l8.

In the operation of the feeding mechanism, an

a J ammunition belt is introduced into the receiving chute 2, the cartridges are removed from the belt and fed into the gun through the chute 4, while the empty belt links are discharged through the chute 3 in conventional manner. During this operation, the door 5 is held closed by the engagement of the bifurcated end I! of the latch I5 under the button l8, which engagement is maintained by the spring 8.

Should it become necessary to open the door 5, the operator grasps the loop 23 and pulls it upward against the resistance of the spring 8 until the bifurcation of the latch I 5 is withdrawn from the shank 22 of the button N3. He then rotates the latch sidewise against the yielding r sistance provided by the inclined portion 25 or 26 of spring 8 so as to swing the end of the latch l5 out from under the button l8. Then the door is free to be opened against the pressure of the spring 8 by outward traction on the loop 23. It will be appreciated that this entire operation may be very quickly accomplished by the use of one hand only of the operator. When the necessary inspection or release of the belt feeding mechanism has been accomplished, the door is closed and locked in position by a reversal of the stepsinvolved in releasing and opening the door. Since the three functions of the spring 8 of yieldingly urging the door closed, pressing the latch downward and resisting pivotal movement of the latch are each performed by a different type of deformation of the spring, it will be appreciated' that the optimum condition with respent to each function may be readily secured by appropriate formation of the spring without adversely afiecting its performance of the other functions. Thus, the stiffness of the spring with respect to hinging movement of the door may be adjusted by providing a suitable number of convol utions of the spring about the tie-rod I. The downward pressure of the spring on the latch [53 maybe ad justed by proper selection of the length of the loops connecting the mid portion of the spring to the terminal portions 9 and H thereof, while the resistance of the spring to pivotal movement of the latch may be adjusted by proper inclination of the portions 25, 26 0f the spring.

Although but one embodiment of the invention has been shown and described in detail, it will be understood that other embodiments are possible and that changes may be made in the proportions and arrangement of the parts without departing from the spirit of the invention as defined in the claims appended hereto.

What is claimed is:

1. A latch mechanism, adapted for use on a hinged door of a discharge chute comprising, a spring bearing on the door and pressing it toward closed position, a catch fixed on the chute, a latch pivotally and slidably mounted on the door in position to engage at one end in the catch when the door is closed, said latch and catch being so formed and mounted that release is accomplished by first a sliding Withdrawal and then a pivotal disengagement of the latch, said spring being formed to engage the latch and resist both the sliding withdrawal and the pivotal movement of the latch.

2. A latch mechanism, adapted for use on a. hinged door of a discharge chute comprising, a spring pressing the door closed, a latch pivoted on the door with limited freedom for sliding movement, having a bifurcated end, a flanged catch member fixed to the chute, said spring having a portion engaging the latch urging the bifurcated end thereof into engagement with the shank of the catch beneaththe flange thereof, and resisting rotation of the latch.

HARRISON C. GILBERT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 294,785 Jackson Mar. 11, 1884 702,901 Woodman June 17, 1902 1,968,761 Groom July 31, 1934 2,335,449 Salisbury Nov. 30, 1943 2,156,110 Brukner Apr. 25,1939 1,067,300 Booth July 15, 1913 

